This invention relates to an apparatus for stacking generic sheet-like elements such as sheets, hides, boards, and the like.
As is known, in order to unload sheet-like elements such as hides, sheets, boards, and the like from a continuously moving conveyor belt, purely manual techniques are currently used whereby an operator picks up the various sheet-like elements and locates them on a stand or shelf which acts as a collector.
It will be appreciated that such a procedure involves a significant labor input which reflects heavily on production costs.
In an attempt to obviate such drawbacks, apparatuses have been provided which allow the various sheet-like elements to be laid in a substantially automatic fashion on the stand or shelf. With such apparatuses, the shelf is translated continuously in the sheet-like element's feeding direction, relatively to the conveyor belt, thereby an oncoming sheet-like element is practically deposited on the stand which moves relatively to it.
However, this approach has various disadvantages, the first of which is that the continuous movement of the stand whereon the sheet-like elements are stacked may create unbalance in the stack of sheet-like elements which may then be dropped. A further disadvantage is that in general the shelf and conveyor belt lie in different planes which, in general, are spaced far apart, thereby causing the sheet-like element to practically fall like a dead leaf onto the shelf or stand, thereby creating significant errors in the positioning of the sheet-like elements.
Another prior approach, which is in practice the kinematic reverse of the former, provides for the shelf to be held stationary, thus reducing the risk of the stack of sheet-like elements collapsing, and for the conveyor belt to be continuously moved relatively to the shelf as the various sheet-like elements are being fed.
However, this approach is very complicated to realize by virtue of the large moving masses involved, which comprise entire displacement movement of the actual feed mechanism.
Another disadvantage shared by the embodiments just described is that such apparatuses are of large size because the stand and conveyor have a combined length which is at least twice the length of the sheet-like element to be stacked.